It is one of the immunological medical tests that can be used to detect the presence of either specific antibody or specific antigen in a patient’s serum. This test is based on whether complement fixation occurs or not. It is used for various purposes such as diagnosing infections caused by microbes that are not easily … Read more
Pseudomonads are a large group of aerobic, Gram-negative, non-fermentative bacilli. This contains over 200 species that were originally contained within the genus Pseudomonas. Some of them produce water soluble pigments which get diffused through the culture medium. The members are generally saprophytic in nature. They are widely distributed in different habitat like in soil, water, … Read more
Sulfur is an essential nutrient for plant as well as animal. It is one of the constituent of many proteins and co-factors. The major reserve of the element is the soil. Sulfur compounds can be used in various ways as oxidants or reductants in microbial respiration. The dominance of one or another transformation is governed … Read more
Experience has confirmed that some organisms are more hazardous to handle. They are more likely to infect laboratory workers than others. World Health Organization (WHO) has classified the microorganisms (i.e., those associated with safety measures in medical laboratory) into four risk groups. The list of organisms in each group may not be same for every … Read more
S.N Food borne infection Food borne intoxication 1. It is caused due to the ingestion of pathogen in contaminated food. It is caused due to ingestion of toxin produced by pathogen along with contaminated food. 2. Microorganism itself or along with toxin involved. Only microbial product i.e. toxin is involved. 3. Number of pathogen increases … Read more
Entamoeba histolytica is a common parasite in the large intestine of humans, certain other primates and some other animals. This parasite is responsible to cause amoebiasis which is the third leading parasitic cause of death in the developing countries. Tropohozoites of this parasite are found in the mucous and sub-mucous layers of the large intestine … Read more
The cyclic movement of nitrogen between atmosphere and living organisms or the exchange of nitrogen between atmosphere and living organisms is known as nitrogen cycle. It is also one of the gaseous-cycle. Nitrogen is the most essential element for almost all forms of life. Living organisms need nitrogen atoms to make amino acids, proteins, enzymes, … Read more
It is heat treatment that kills part but not all of the microorganisms present. It usually involves the application of temperatures below 1000C. The heating may be by means of steam, hot water, dry heat, or electric currents and the products are cooled promptly after the heat treatment. Pasteurization is used in following conditions: When … Read more
Most kinds of food are readily decomposed by microorganisms unless special methods are used for their preservation. The chief methods of food preservation are as follows: Asepsis, or keeping out microorganisms. Removal of microorganisms. Maintenance of anaerobic conditions, e.g., in a sealed, evacuated container. Use of high temperatures. Use of low temperatures. Drying; this includes … Read more
The prevalence of tuberculous infection may be estimated by the use of the tuberculin test in contradistinction to the clinical disease. The positive test indicates that the individual has been infected by the tubercle bacillus sometime without necessarily showing overt signs or symptoms of disease. A standardized tuberculin is available now through the World Health … Read more